Electrochemical energy storage systems, such as batteries, supercapacitors and the like, have been widely proposed for large-scale energy storage applications. Various battery designs, including flow batteries, have been considered for this purpose. Compared to other types of electrochemical energy storage systems, flow batteries can be advantageous, particularly for large-scale applications, due to their ability to decouple the parameters of power density and energy density from one another.
Flow batteries generally include negative and positive active materials in corresponding electrolyte solutions, which are flowed separately across opposing sides of a membrane or separator in an electrochemical cell containing negative and positive electrodes. The flow battery is charged or discharged through electrochemical reactions of the active materials that occur inside the two half-cells. As used herein, the terms “active material,” “electroactive material,” “redox-active material” or variants thereof will synonymously refer to materials that undergo a change in oxidation state during operation of a flow battery or like electrochemical energy storage system (i.e., during charging or discharging). A full electrochemical cell contains two half-cells (i.e., a positive half-cell and a negative half-cell) that are separated by the separator material.
In order to increase the amount of energy that can be stored and released by a flow battery, a plurality of individual electrochemical cells can be placed in electrical communication with one another. Placing the individual electrochemical cells in electrical communication with one another typically involves positioning the individual electrochemical cells in a “cell stack” or “electrochemical stack” with a bipolar plate establishing electrical communication between adjacent electrochemical cells.
Design and fabrication of individual electrochemical cells typically involves the mating of various “hard goods” and “soft goods” together with one another. Soft goods can include the separator material, electrodes, and seals used to contain the electrolyte solution in a desired area within the electrochemical cell. Hard goods can include the bipolar plate and any framing materials used to contain the soft goods. Conventional manufacturing processes for electrochemical cells oftentimes mold and/or machine the hard goods for the individual cells, and cell assembly is then completed by positioning the soft goods manually or with semi-automated pick-and-place processes. Such manual and semi-automated batch processes for assembling electrochemical cells represent a rate-limiting manufacturing step that is largely incapable of producing high throughput. Even the molding and machining processes for the hard goods can become problematic if construction of a significantly large number of individual electrochemical cells is needed. Moreover, batch manufacturing processes of the foregoing types can be highly susceptible to producing faulty cells as a result of operator error. Accordingly, manufacturing processes for producing electrochemical cells and cells stacks remain laborious, time-consuming, and expensive.
In view of the foregoing, electrochemical cell designs that are compatible with high-throughput manufacturing processes would be highly desirable in the art. The present disclosure satisfies the foregoing need and provides related advantages as well.